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DRIVER SERVICES

Driving Under the Influence (DUI)

Alcohol is the number one killer on American roadways. Alcohol affects your vision and slows your reaction time so it takes longer to act in an emergency. Alcohol affects your driving even if you are below the level of illegal intoxication. Drinking even a small amount of alcohol increases your chances of causing a crash. Do not drink and drive.

Blood-Alcohol Concentration (BAC)

Blood-alcohol concentration is a measurement of the amount of alcohol in your system based on a test of your breath, blood or urine. It is illegal to drive if your BAC is .08 percent or more. However, you can be convicted of Driving Under the Influence (DUI) if your BAC is less than .08 percent and your driving ability is impaired. Your BAC can be affected by:

The amount you drink — 12 ounces of beer, 5 ounces of wine or 1.5 ounces of hard liquor contain the same amount of alcohol.

Your body weight or size. Usually, heavier people have more blood and body fluids to dilute the alcohol.

Other factors affect your reaction to alcohol, including the food you have eaten, your tolerance of alcohol and any drugs you may have taken. Time is the only way to remove the effects of alcohol. Food, coffee and showers do not speed up the elimination of alcohol from your body.

Medical Cannabis (Marijuana)

Illinois allows for the use of marijuana for medicinal purposes. Individuals authorized to use marijuana must be 18 years of age or older, registered with the Department of Public Health and must secure a written certification from a physician licensed in Illinois. The Department of Public Health will issue a registry identification card and a notation will be made on the registrant’s driving record.

A driver may not operate a motor vehicle while under the influence of marijuana prescribed for medicinal purposes and may not transport medicinal marijuana in a vehicle unless it is stored in a tamper-evident container and kept in an area that is inaccessible while the vehicle is in motion. If a police officer stops a vehicle driven by a person who holds a medical cannabis registry card and the officer has reasonable suspicion to believe the person is impaired by the use of cannabis, the driver must submit to field sobriety testing. Refusal to submit to testing or failure of the field sobriety tests will result in the suspension of the person’s driver’s license.

Driving while impaired by the use of cannabis, or driving with an open container may result in the loss of driving privileges as well as the revocation of the driver's medical cannabis card.

Other Drugs

In addition to alcohol and marijuana, many prescription and nonprescription drugs impair safe driving.